Events since 2000 underscore the utter unpredictability of the future. The 2000 election was the first in 112 years in which a president lost the popular vote but captured enough states to win the electoral vote. It took five weeks to determine the election's outcome, which hinged on a few hundred votes in Florida. By a 5-4 majority, the U.S. Supreme Court halted a recount ordered by the Florida Supreme Court on the grounds that it violated the principle that all votes must be treated equally and that there was not enough time to conduct a new manual recount that would meet constitutional muster.

The new president, George W. Bush, described himself as a “compassionate conservative” committed to the principles of limited government, personal responsibility, strong families, and local control. He proposed to improve public schools by insisting on competency testing. Under his proposed “faith-based initiative,” religious institutions would be able to compete for government funds to provide social services. A major legislative success involved cutting taxes. But terrorist attacks that took place on September 11, 2001, would reshape the direction of his presidency.

On September 11, hijackers turned commercial airlines into missiles and attacked key symbols of American economic and military might. These hideous attacks leveled the World Trade Center towers in New York, destroyed part of the Pentagon, and left Americans in a mood similar to that which the country experienced after the devastating Japanese attack on the American fleet at Pearl Harbor in 1941.

In retaliation for the attacks, a U.S.-led coalition overthrew the Taliban government of Afghanistan, which harbored al-Qaeda, the terrorist networks that had staged the assaults. Congress enacted legislation giving law enforcement agencies broader authority to detain or deport aliens and to conduct wiretaps. It also created a cabinet-level Department of Homeland Security to reduce the country's vulnerability to terrorism.

On March 20, 2003, the United States and a coalition of Allies went to war against Iraq, one of the countries (along with Iran and North Korea) that President Bush regarded as part of an "axis of evil." The invasion did not receive United Nations' backing, which might have provided greater international legitimacy to take out Hussein's regime. Iraq’s military, severely weakened during the 1991 Persian Gulf War, quickly collapsed before coalition forces. On May 1, 2003, Bush told the American people that “major combat operations in Iraq have ended.” At that juncture, 137 American military personnel had been killed.

More than three years after toppling Hussein's government, U.S. and coalition troops were fighting insurgent forces, made up of remnants of the old regime, disgruntled Sunni and Shiite Iraqis, and terrorists who had infiltrated the country. By March 2006, more than 2,300 American troops had died in Iraq.

In 2004, as in the election of 2000, a single state decided the outcome of the presidency, based on the distribution of electoral votes. Ohio’s 20 votes gave Bush the margin of victory over Sen. John Kerry of Massachusetts. Still, with a 3.5 million popular vote margin, Bush won the first outright majority in the popular vote for president in 16 years, and the Republican Party succeeded in expanding GOP majorities in the House and Senate.

The Republicans succeeded by galvanizing more supporters than did the Democrats, especially among religious conservatives concerned about moral values. It seemed likely that the decision by the Massachusetts Supreme Court to legalize gay marriage--which led 11 states to vote on initiatives banning gay marriage--helped the Bush campaign mobilize religious voters.

President Bush's top priority in his second term was to end the insurgency in Iraq. He also announced an aggressive domestic policy agenda that included promoting energy production and allowing younger workers to divert part of their Social Security taxes into personal investment accounts, making permanent the $1.9 trillion tax cuts he won in his first term. Although he had several successes, including a revamping of bankruptcy laws, placing restrictions on class-action lawsuits, and proposing energy legislation, many of his other proposals, especially his plan to reform Social Security, faced stiff resistance from Democrats in Congress.